1. Field of the Invention
The present invention relates to improvements in a rear portion structure for a saddle type vehicle.
2. Description of Background Art
An accommodation structure for a saddle type vehicle which is limited in disposition space for parts and articles has been proposed which includes a disposition space for parts provided above a rear fender below a seat on which a rider is to be seated. See, for example, Japanese Patent No. 4216965 (FIG. 6).
As shown in the FIG. 6 of Japanese Patent No. 4216965, below a seat supported by a pair of left and right seat rails (38) (a reference character in parentheses represents a reference character used in Japanese Patent No. 4216965) a battery accommodation section (87) is provided. This battery accommodation section (87) is configured from a pair of left and right side plates (82) and a bottom plate (83) extending between lower ends of the left and right paired side plates (82). The side plates (82) and the bottom plate (83) are formed integrally with a rear fender (46). The rear fender (46) is a molded resin part (Japanese Patent No. 4216965, paragraph number [0032]).
In particular, the side plates (82) of the battery accommodation section (87) first extend upwardly from the bottom plate (83) and then extend outwardly in a vehicle widthwise direction once, and then extend upwardly at outer positions with respect to the seat rails (38) in such a manner as to bypass the seat rails (38). On such side plates (82) as described above, a partition wall (89) is provided which is branched at an inner position with respect to the seat rails (38) in the vehicle widthwise direction and extends upwardly. A wiring groove (90), along which wire harnesses (91, 92) pass, is formed between the partition wall (89) and upper portions of the side plates (82).
Since the rear fender (46) is a molded resin part, also the battery accommodation section (87) is a molded resin part. A molded resin part is generally fabricated by injection molding using a metal mold. In order to smoothly release the molded article from the metal mold, it is necessary to set the distance between the left and light side plates (82) which become molded articles such that it is equal to the width of the bottom plate (83) or it increases upwardly such that it becomes greater than the width of the bottom plate (83).
Here, a structure wherein the left and right side plates (82) extend vertically upwardly from the end portions of the bottom plate (83) and another structure wherein the side plates (82) extend obliquely upwardly outwards in the vehicle widthwise direction from the end portions of the bottom plate (83) are compared with each other in terms of the accommodation space (space) for accommodating parts and so forth and the foot grounding property of a rider.
Where the width of the bottom plate is equal, if the structure wherein the left and right side plates (82) extend vertically upwardly from the end portions of the bottom plate (83) is applied, then it is easy to decrease the width of the seat in the proximity of the upper ends of the side plates in comparison with the structure wherein the side plates (82) extend obliquely upwardly outwards in the vehicle widthwise direction from the end portions of the bottom plate (83). Therefore, since the width of the seat decreases, the accommodation space decreases although the foot grounding property of a rider is enhanced.
On the other hand, if the structure wherein the side plates (82) extend obliquely upwardly outwards in the vehicle widthwise direction from the end portions of the bottom plate (83) is applied, then the accommodation space can be increased readily in comparison with the structure wherein the left and right side plates (82) extend vertically upwardly from the end portions of the bottom plate (83). However, this increases the width of the seat, and room is left for improvement in the foot grounding property of a rider.
However, while further improvement is demanded for a saddle type vehicle, a rear portion structure for a saddle type vehicle is demanded which can satisfy both of the foot grounding property of a rider and assurance of an accommodation space for accommodating parts.